asan_rtl.cc revision 745dd0d296e7bef712df4b5c7f86c72534953738
1651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines//===-- asan_rtl.cc -------------------------------------------------------===// 2651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// 3651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// The LLVM Compiler Infrastructure 4651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// 5651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// This file is distributed under the University of Illinois Open Source 6651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// License. See LICENSE.TXT for details. 7651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// 8651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines//===----------------------------------------------------------------------===// 9651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// 10651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// This file is a part of AddressSanitizer, an address sanity checker. 11651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// 12651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines// Main file of the ASan run-time library. 13651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines//===----------------------------------------------------------------------===// 14651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_allocator.h" 15651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_interceptors.h" 16651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_internal.h" 17651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_mapping.h" 18651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_poisoning.h" 19651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_report.h" 20651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_stack.h" 21651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_stats.h" 22651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "asan_thread.h" 23651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "sanitizer_common/sanitizer_atomic.h" 24651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "sanitizer_common/sanitizer_flags.h" 25651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "sanitizer_common/sanitizer_libc.h" 26651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "sanitizer_common/sanitizer_symbolizer.h" 27651f13cea278ec967336033dd032faef0e9fc2ecStephen Hines#include "lsan/lsan_common.h" 28 29namespace __asan { 30 31uptr AsanMappingProfile[kAsanMappingProfileSize]; 32 33static void AsanDie() { 34 static atomic_uint32_t num_calls; 35 if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) { 36 // Don't die twice - run a busy loop. 37 while (1) { } 38 } 39 if (flags()->sleep_before_dying) { 40 Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying); 41 SleepForSeconds(flags()->sleep_before_dying); 42 } 43 if (flags()->unmap_shadow_on_exit) { 44 if (kMidMemBeg) { 45 UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg); 46 UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd); 47 } else { 48 UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg); 49 } 50 } 51 if (death_callback) 52 death_callback(); 53 if (flags()->abort_on_error) 54 Abort(); 55 internal__exit(flags()->exitcode); 56} 57 58static void AsanCheckFailed(const char *file, int line, const char *cond, 59 u64 v1, u64 v2) { 60 Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", 61 file, line, cond, (uptr)v1, (uptr)v2); 62 // FIXME: check for infinite recursion without a thread-local counter here. 63 PRINT_CURRENT_STACK(); 64 Die(); 65} 66 67// -------------------------- Flags ------------------------- {{{1 68static const int kDefaultMallocContextSize = 30; 69 70Flags asan_flags_dont_use_directly; // use via flags(). 71 72static const char *MaybeCallAsanDefaultOptions() { 73 return (&__asan_default_options) ? __asan_default_options() : ""; 74} 75 76static const char *MaybeUseAsanDefaultOptionsCompileDefiniton() { 77#ifdef ASAN_DEFAULT_OPTIONS 78// Stringize the macro value. 79# define ASAN_STRINGIZE(x) #x 80# define ASAN_STRINGIZE_OPTIONS(options) ASAN_STRINGIZE(options) 81 return ASAN_STRINGIZE_OPTIONS(ASAN_DEFAULT_OPTIONS); 82#else 83 return ""; 84#endif 85} 86 87static void ParseFlagsFromString(Flags *f, const char *str) { 88 ParseCommonFlagsFromString(str); 89 CHECK((uptr)common_flags()->malloc_context_size <= kStackTraceMax); 90 91 ParseFlag(str, &f->quarantine_size, "quarantine_size"); 92 ParseFlag(str, &f->verbosity, "verbosity"); 93 ParseFlag(str, &f->redzone, "redzone"); 94 CHECK_GE(f->redzone, 16); 95 CHECK(IsPowerOfTwo(f->redzone)); 96 97 ParseFlag(str, &f->debug, "debug"); 98 ParseFlag(str, &f->report_globals, "report_globals"); 99 ParseFlag(str, &f->check_initialization_order, "check_initialization_order"); 100 101 ParseFlag(str, &f->replace_str, "replace_str"); 102 ParseFlag(str, &f->replace_intrin, "replace_intrin"); 103 ParseFlag(str, &f->mac_ignore_invalid_free, "mac_ignore_invalid_free"); 104 ParseFlag(str, &f->use_fake_stack, "use_fake_stack"); 105 ParseFlag(str, &f->max_malloc_fill_size, "max_malloc_fill_size"); 106 ParseFlag(str, &f->malloc_fill_byte, "malloc_fill_byte"); 107 ParseFlag(str, &f->exitcode, "exitcode"); 108 ParseFlag(str, &f->allow_user_poisoning, "allow_user_poisoning"); 109 ParseFlag(str, &f->sleep_before_dying, "sleep_before_dying"); 110 ParseFlag(str, &f->handle_segv, "handle_segv"); 111 ParseFlag(str, &f->allow_user_segv_handler, "allow_user_segv_handler"); 112 ParseFlag(str, &f->use_sigaltstack, "use_sigaltstack"); 113 ParseFlag(str, &f->check_malloc_usable_size, "check_malloc_usable_size"); 114 ParseFlag(str, &f->unmap_shadow_on_exit, "unmap_shadow_on_exit"); 115 ParseFlag(str, &f->abort_on_error, "abort_on_error"); 116 ParseFlag(str, &f->print_stats, "print_stats"); 117 ParseFlag(str, &f->print_legend, "print_legend"); 118 ParseFlag(str, &f->atexit, "atexit"); 119 ParseFlag(str, &f->disable_core, "disable_core"); 120 ParseFlag(str, &f->allow_reexec, "allow_reexec"); 121 ParseFlag(str, &f->print_full_thread_history, "print_full_thread_history"); 122 ParseFlag(str, &f->log_path, "log_path"); 123 ParseFlag(str, &f->poison_heap, "poison_heap"); 124 ParseFlag(str, &f->alloc_dealloc_mismatch, "alloc_dealloc_mismatch"); 125 ParseFlag(str, &f->use_stack_depot, "use_stack_depot"); 126 ParseFlag(str, &f->strict_memcmp, "strict_memcmp"); 127 ParseFlag(str, &f->strict_init_order, "strict_init_order"); 128 ParseFlag(str, &f->detect_leaks, "detect_leaks"); 129} 130 131void InitializeFlags(Flags *f, const char *env) { 132 CommonFlags *cf = common_flags(); 133 cf->external_symbolizer_path = GetEnv("ASAN_SYMBOLIZER_PATH"); 134 cf->symbolize = true; 135 cf->malloc_context_size = kDefaultMallocContextSize; 136 cf->fast_unwind_on_fatal = false; 137 cf->fast_unwind_on_malloc = true; 138 cf->strip_path_prefix = ""; 139 cf->handle_ioctl = false; 140 141 internal_memset(f, 0, sizeof(*f)); 142 f->quarantine_size = (ASAN_LOW_MEMORY) ? 1UL << 26 : 1UL << 28; 143 f->verbosity = 0; 144 f->redzone = 16; 145 f->debug = false; 146 f->report_globals = 1; 147 f->check_initialization_order = false; 148 f->replace_str = true; 149 f->replace_intrin = true; 150 f->mac_ignore_invalid_free = false; 151 f->use_fake_stack = true; 152 f->max_malloc_fill_size = 0x1000; // By default, fill only the first 4K. 153 f->malloc_fill_byte = 0xbe; 154 f->exitcode = ASAN_DEFAULT_FAILURE_EXITCODE; 155 f->allow_user_poisoning = true; 156 f->sleep_before_dying = 0; 157 f->handle_segv = ASAN_NEEDS_SEGV; 158 f->allow_user_segv_handler = false; 159 f->use_sigaltstack = false; 160 f->check_malloc_usable_size = true; 161 f->unmap_shadow_on_exit = false; 162 f->abort_on_error = false; 163 f->print_stats = false; 164 f->print_legend = true; 165 f->atexit = false; 166 f->disable_core = (SANITIZER_WORDSIZE == 64); 167 f->allow_reexec = true; 168 f->print_full_thread_history = true; 169 f->log_path = 0; 170 f->poison_heap = true; 171 // Turn off alloc/dealloc mismatch checker on Mac for now. 172 // TODO(glider): Fix known issues and enable this back. 173 f->alloc_dealloc_mismatch = (SANITIZER_MAC == 0);; 174 f->use_stack_depot = true; 175 f->strict_memcmp = true; 176 f->strict_init_order = false; 177 f->detect_leaks = false; 178 179 // Override from compile definition. 180 ParseFlagsFromString(f, MaybeUseAsanDefaultOptionsCompileDefiniton()); 181 182 // Override from user-specified string. 183 ParseFlagsFromString(f, MaybeCallAsanDefaultOptions()); 184 if (flags()->verbosity) { 185 Report("Using the defaults from __asan_default_options: %s\n", 186 MaybeCallAsanDefaultOptions()); 187 } 188 189 // Override from command line. 190 ParseFlagsFromString(f, env); 191 192#if !CAN_SANITIZE_LEAKS 193 if (f->detect_leaks) { 194 Report("%s: detect_leaks is not supported on this platform.\n", 195 SanitizerToolName); 196 f->detect_leaks = false; 197 } 198#endif 199 200 if (f->detect_leaks && !f->use_stack_depot) { 201 Report("%s: detect_leaks is ignored (requires use_stack_depot).\n", 202 SanitizerToolName); 203 f->detect_leaks = false; 204 } 205} 206 207// -------------------------- Globals --------------------- {{{1 208int asan_inited; 209bool asan_init_is_running; 210void (*death_callback)(void); 211 212#if !ASAN_FIXED_MAPPING 213uptr kHighMemEnd, kMidMemBeg, kMidMemEnd; 214#endif 215 216// -------------------------- Misc ---------------- {{{1 217void ShowStatsAndAbort() { 218 __asan_print_accumulated_stats(); 219 Die(); 220} 221 222// ---------------------- mmap -------------------- {{{1 223// Reserve memory range [beg, end]. 224static void ReserveShadowMemoryRange(uptr beg, uptr end) { 225 CHECK_EQ((beg % GetPageSizeCached()), 0); 226 CHECK_EQ(((end + 1) % GetPageSizeCached()), 0); 227 uptr size = end - beg + 1; 228 void *res = MmapFixedNoReserve(beg, size); 229 if (res != (void*)beg) { 230 Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. " 231 "Perhaps you're using ulimit -v\n", size); 232 Abort(); 233 } 234} 235 236// --------------- LowLevelAllocateCallbac ---------- {{{1 237static void OnLowLevelAllocate(uptr ptr, uptr size) { 238 PoisonShadow(ptr, size, kAsanInternalHeapMagic); 239} 240 241// -------------------------- Run-time entry ------------------- {{{1 242// exported functions 243#define ASAN_REPORT_ERROR(type, is_write, size) \ 244extern "C" NOINLINE INTERFACE_ATTRIBUTE \ 245void __asan_report_ ## type ## size(uptr addr); \ 246void __asan_report_ ## type ## size(uptr addr) { \ 247 GET_CALLER_PC_BP_SP; \ 248 __asan_report_error(pc, bp, sp, addr, is_write, size); \ 249} 250 251ASAN_REPORT_ERROR(load, false, 1) 252ASAN_REPORT_ERROR(load, false, 2) 253ASAN_REPORT_ERROR(load, false, 4) 254ASAN_REPORT_ERROR(load, false, 8) 255ASAN_REPORT_ERROR(load, false, 16) 256ASAN_REPORT_ERROR(store, true, 1) 257ASAN_REPORT_ERROR(store, true, 2) 258ASAN_REPORT_ERROR(store, true, 4) 259ASAN_REPORT_ERROR(store, true, 8) 260ASAN_REPORT_ERROR(store, true, 16) 261 262#define ASAN_REPORT_ERROR_N(type, is_write) \ 263extern "C" NOINLINE INTERFACE_ATTRIBUTE \ 264void __asan_report_ ## type ## _n(uptr addr, uptr size); \ 265void __asan_report_ ## type ## _n(uptr addr, uptr size) { \ 266 GET_CALLER_PC_BP_SP; \ 267 __asan_report_error(pc, bp, sp, addr, is_write, size); \ 268} 269 270ASAN_REPORT_ERROR_N(load, false) 271ASAN_REPORT_ERROR_N(store, true) 272 273// Force the linker to keep the symbols for various ASan interface functions. 274// We want to keep those in the executable in order to let the instrumented 275// dynamic libraries access the symbol even if it is not used by the executable 276// itself. This should help if the build system is removing dead code at link 277// time. 278static NOINLINE void force_interface_symbols() { 279 volatile int fake_condition = 0; // prevent dead condition elimination. 280 // __asan_report_* functions are noreturn, so we need a switch to prevent 281 // the compiler from removing any of them. 282 switch (fake_condition) { 283 case 1: __asan_report_load1(0); break; 284 case 2: __asan_report_load2(0); break; 285 case 3: __asan_report_load4(0); break; 286 case 4: __asan_report_load8(0); break; 287 case 5: __asan_report_load16(0); break; 288 case 6: __asan_report_store1(0); break; 289 case 7: __asan_report_store2(0); break; 290 case 8: __asan_report_store4(0); break; 291 case 9: __asan_report_store8(0); break; 292 case 10: __asan_report_store16(0); break; 293 case 12: __asan_register_globals(0, 0); break; 294 case 13: __asan_unregister_globals(0, 0); break; 295 case 14: __asan_set_death_callback(0); break; 296 case 15: __asan_set_error_report_callback(0); break; 297 case 16: __asan_handle_no_return(); break; 298 case 17: __asan_address_is_poisoned(0); break; 299 case 18: __asan_get_allocated_size(0); break; 300 case 19: __asan_get_current_allocated_bytes(); break; 301 case 20: __asan_get_estimated_allocated_size(0); break; 302 case 21: __asan_get_free_bytes(); break; 303 case 22: __asan_get_heap_size(); break; 304 case 23: __asan_get_ownership(0); break; 305 case 24: __asan_get_unmapped_bytes(); break; 306 case 25: __asan_poison_memory_region(0, 0); break; 307 case 26: __asan_unpoison_memory_region(0, 0); break; 308 case 27: __asan_set_error_exit_code(0); break; 309 case 28: __asan_stack_free(0, 0, 0); break; 310 case 29: __asan_stack_malloc(0, 0); break; 311 case 30: __asan_before_dynamic_init(0); break; 312 case 31: __asan_after_dynamic_init(); break; 313 case 32: __asan_poison_stack_memory(0, 0); break; 314 case 33: __asan_unpoison_stack_memory(0, 0); break; 315 case 34: __asan_region_is_poisoned(0, 0); break; 316 case 35: __asan_describe_address(0); break; 317 } 318} 319 320static void asan_atexit() { 321 Printf("AddressSanitizer exit stats:\n"); 322 __asan_print_accumulated_stats(); 323 // Print AsanMappingProfile. 324 for (uptr i = 0; i < kAsanMappingProfileSize; i++) { 325 if (AsanMappingProfile[i] == 0) continue; 326 Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]); 327 } 328} 329 330static void InitializeHighMemEnd() { 331#if !ASAN_FIXED_MAPPING 332#if SANITIZER_WORDSIZE == 64 333# if defined(__powerpc64__) 334 // FIXME: 335 // On PowerPC64 we have two different address space layouts: 44- and 46-bit. 336 // We somehow need to figure our which one we are using now and choose 337 // one of 0x00000fffffffffffUL and 0x00003fffffffffffUL. 338 // Note that with 'ulimit -s unlimited' the stack is moved away from the top 339 // of the address space, so simply checking the stack address is not enough. 340 kHighMemEnd = (1ULL << 44) - 1; // 0x00000fffffffffffUL 341# else 342 kHighMemEnd = (1ULL << 47) - 1; // 0x00007fffffffffffUL; 343# endif 344#else // SANITIZER_WORDSIZE == 32 345 kHighMemEnd = (1ULL << 32) - 1; // 0xffffffff; 346#endif // SANITIZER_WORDSIZE 347#endif // !ASAN_FIXED_MAPPING 348} 349 350static void ProtectGap(uptr a, uptr size) { 351 CHECK_EQ(a, (uptr)Mprotect(a, size)); 352} 353 354static void PrintAddressSpaceLayout() { 355 Printf("|| `[%p, %p]` || HighMem ||\n", 356 (void*)kHighMemBeg, (void*)kHighMemEnd); 357 Printf("|| `[%p, %p]` || HighShadow ||\n", 358 (void*)kHighShadowBeg, (void*)kHighShadowEnd); 359 if (kMidMemBeg) { 360 Printf("|| `[%p, %p]` || ShadowGap3 ||\n", 361 (void*)kShadowGap3Beg, (void*)kShadowGap3End); 362 Printf("|| `[%p, %p]` || MidMem ||\n", 363 (void*)kMidMemBeg, (void*)kMidMemEnd); 364 Printf("|| `[%p, %p]` || ShadowGap2 ||\n", 365 (void*)kShadowGap2Beg, (void*)kShadowGap2End); 366 Printf("|| `[%p, %p]` || MidShadow ||\n", 367 (void*)kMidShadowBeg, (void*)kMidShadowEnd); 368 } 369 Printf("|| `[%p, %p]` || ShadowGap ||\n", 370 (void*)kShadowGapBeg, (void*)kShadowGapEnd); 371 if (kLowShadowBeg) { 372 Printf("|| `[%p, %p]` || LowShadow ||\n", 373 (void*)kLowShadowBeg, (void*)kLowShadowEnd); 374 Printf("|| `[%p, %p]` || LowMem ||\n", 375 (void*)kLowMemBeg, (void*)kLowMemEnd); 376 } 377 Printf("MemToShadow(shadow): %p %p %p %p", 378 (void*)MEM_TO_SHADOW(kLowShadowBeg), 379 (void*)MEM_TO_SHADOW(kLowShadowEnd), 380 (void*)MEM_TO_SHADOW(kHighShadowBeg), 381 (void*)MEM_TO_SHADOW(kHighShadowEnd)); 382 if (kMidMemBeg) { 383 Printf(" %p %p", 384 (void*)MEM_TO_SHADOW(kMidShadowBeg), 385 (void*)MEM_TO_SHADOW(kMidShadowEnd)); 386 } 387 Printf("\n"); 388 Printf("red_zone=%zu\n", (uptr)flags()->redzone); 389 Printf("malloc_context_size=%zu\n", 390 (uptr)common_flags()->malloc_context_size); 391 392 Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE); 393 Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY); 394 Printf("SHADOW_OFFSET: %zx\n", (uptr)SHADOW_OFFSET); 395 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7); 396 if (kMidMemBeg) 397 CHECK(kMidShadowBeg > kLowShadowEnd && 398 kMidMemBeg > kMidShadowEnd && 399 kHighShadowBeg > kMidMemEnd); 400} 401 402} // namespace __asan 403 404// ---------------------- Interface ---------------- {{{1 405using namespace __asan; // NOLINT 406 407#if !SANITIZER_SUPPORTS_WEAK_HOOKS 408extern "C" { 409SANITIZER_WEAK_ATTRIBUTE SANITIZER_INTERFACE_ATTRIBUTE 410const char* __asan_default_options() { return ""; } 411} // extern "C" 412#endif 413 414int NOINLINE __asan_set_error_exit_code(int exit_code) { 415 int old = flags()->exitcode; 416 flags()->exitcode = exit_code; 417 return old; 418} 419 420void NOINLINE __asan_handle_no_return() { 421 int local_stack; 422 AsanThread *curr_thread = GetCurrentThread(); 423 CHECK(curr_thread); 424 uptr PageSize = GetPageSizeCached(); 425 uptr top = curr_thread->stack_top(); 426 uptr bottom = ((uptr)&local_stack - PageSize) & ~(PageSize-1); 427 static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M 428 if (top - bottom > kMaxExpectedCleanupSize) { 429 static bool reported_warning = false; 430 if (reported_warning) 431 return; 432 reported_warning = true; 433 Report("WARNING: ASan is ignoring requested __asan_handle_no_return: " 434 "stack top: %p; bottom %p; size: %p (%zd)\n" 435 "False positive error reports may follow\n" 436 "For details see " 437 "http://code.google.com/p/address-sanitizer/issues/detail?id=189\n", 438 top, bottom, top - bottom, top - bottom); 439 return; 440 } 441 PoisonShadow(bottom, top - bottom, 0); 442} 443 444void NOINLINE __asan_set_death_callback(void (*callback)(void)) { 445 death_callback = callback; 446} 447 448void __asan_init() { 449 if (asan_inited) return; 450 SanitizerToolName = "AddressSanitizer"; 451 CHECK(!asan_init_is_running && "ASan init calls itself!"); 452 asan_init_is_running = true; 453 InitializeHighMemEnd(); 454 455 // Make sure we are not statically linked. 456 AsanDoesNotSupportStaticLinkage(); 457 458 // Install tool-specific callbacks in sanitizer_common. 459 SetDieCallback(AsanDie); 460 SetCheckFailedCallback(AsanCheckFailed); 461 SetPrintfAndReportCallback(AppendToErrorMessageBuffer); 462 463 // Initialize flags. This must be done early, because most of the 464 // initialization steps look at flags(). 465 const char *options = GetEnv("ASAN_OPTIONS"); 466 InitializeFlags(flags(), options); 467 __sanitizer_set_report_path(flags()->log_path); 468 469 if (flags()->verbosity && options) { 470 Report("Parsed ASAN_OPTIONS: %s\n", options); 471 } 472 473 // Re-exec ourselves if we need to set additional env or command line args. 474 MaybeReexec(); 475 476 // Setup internal allocator callback. 477 SetLowLevelAllocateCallback(OnLowLevelAllocate); 478 479 if (flags()->atexit) { 480 Atexit(asan_atexit); 481 } 482 483 // interceptors 484 InitializeAsanInterceptors(); 485 486 ReplaceSystemMalloc(); 487 ReplaceOperatorsNewAndDelete(); 488 489 uptr shadow_start = kLowShadowBeg; 490 if (kLowShadowBeg) shadow_start -= GetMmapGranularity(); 491 uptr shadow_end = kHighShadowEnd; 492 bool full_shadow_is_available = 493 MemoryRangeIsAvailable(shadow_start, shadow_end); 494 495#if SANITIZER_LINUX && defined(__x86_64__) && !ASAN_FIXED_MAPPING 496 if (!full_shadow_is_available) { 497 kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0; 498 kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0; 499 } 500#endif 501 502 if (flags()->verbosity) 503 PrintAddressSpaceLayout(); 504 505 if (flags()->disable_core) { 506 DisableCoreDumper(); 507 } 508 509 if (full_shadow_is_available) { 510 // mmap the low shadow plus at least one page at the left. 511 if (kLowShadowBeg) 512 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd); 513 // mmap the high shadow. 514 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd); 515 // protect the gap. 516 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); 517 } else if (kMidMemBeg && 518 MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) && 519 MemoryRangeIsAvailable(kMidMemEnd + 1, shadow_end)) { 520 CHECK(kLowShadowBeg != kLowShadowEnd); 521 // mmap the low shadow plus at least one page at the left. 522 ReserveShadowMemoryRange(shadow_start, kLowShadowEnd); 523 // mmap the mid shadow. 524 ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd); 525 // mmap the high shadow. 526 ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd); 527 // protect the gaps. 528 ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1); 529 ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1); 530 ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1); 531 } else { 532 Report("Shadow memory range interleaves with an existing memory mapping. " 533 "ASan cannot proceed correctly. ABORTING.\n"); 534 DumpProcessMap(); 535 Die(); 536 } 537 538 InstallSignalHandlers(); 539 // Start symbolizer process if necessary. 540 const char* external_symbolizer = common_flags()->external_symbolizer_path; 541 if (common_flags()->symbolize && external_symbolizer && 542 external_symbolizer[0]) { 543 InitializeExternalSymbolizer(external_symbolizer); 544 } 545 546 // On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited 547 // should be set to 1 prior to initializing the threads. 548 asan_inited = 1; 549 asan_init_is_running = false; 550 551 InitTlsSize(); 552 553 // Create main thread. 554 AsanTSDInit(AsanThread::TSDDtor); 555 AsanThread *main_thread = AsanThread::Create(0, 0); 556 CreateThreadContextArgs create_main_args = { main_thread, 0 }; 557 u32 main_tid = asanThreadRegistry().CreateThread( 558 0, true, 0, &create_main_args); 559 CHECK_EQ(0, main_tid); 560 SetCurrentThread(main_thread); 561 main_thread->ThreadStart(internal_getpid()); 562 force_interface_symbols(); // no-op. 563 564 InitializeAllocator(); 565 566#if CAN_SANITIZE_LEAKS 567 __lsan::InitCommonLsan(); 568 if (flags()->detect_leaks) { 569 Atexit(__lsan::DoLeakCheck); 570 } 571#endif // CAN_SANITIZE_LEAKS 572 573 if (flags()->verbosity) { 574 Report("AddressSanitizer Init done\n"); 575 } 576} 577